Nigel Marriott's Blog

An independent statistician using data to understand our world and to predict the future

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UK General Election 2024 #2 – My Forecasting Model

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My UK General Election 2024 forecasting model will be a top down version which I last used in 2010.  Top down approaches first predict how many seats each party will win in total before seeking to identify which seats each party wins.  This differs from the bottom-up approach I used in 2017 & 2019 where I forecast the outcome for each seat first and then aggregated the forecasts.

Here I explain how my 2024 forecast will be made but it finishes with a warning that I may have to dump my 2024 model in favour of the forecasting approach I used for the 2015 general election.

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UK General Elections #7 – How accurate are voting intention polls? – Revised

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Voting intention polls in the UK are accurate after all!

For years, I’ve observed that UK polls on average underestimate the Conservative vote and overestimate Labour’s vote.  When I converted poll data into forecasts of seats won, I had to first estimate how much polling error there would be.  So what’s changed?  It turns out I was comparing polls to the wrong statistic, namely national vote share.  The correct comparator is in fact average vote share per seat.

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UK Weather Trends #31 – Spring 2024

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Spring 2024 in the UK was the hottest on record.  In some ways this is surprising given it was also the 10th dullest and 6th wettest spring on record which is inconsistent with trends over last 25 years and with the typical correlations seen in spring.  With any other dataset, I would ask for a check on the temperature data to see if it is correct.

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UK Weather Tracker #88 – May 2024

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This was the warmest May on record in the UK which surprised me at first when I saw the data.  Then I saw that where I live (in the South West), it was the 3rd warmest but everywhere else in the UK set a new record.  Notably, the new temperature record was set despite below average sunshine and normal rainfall which may be another reason why I was surprised by the new temperature record.  Finally, as I pointed out in June last year, statistically the previous record looked artificially low relative to the upper decile so a new record is perhaps not that great a surprise.
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UK Weather Tracker #87 – April 2024

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The weather in the UK in April 2024 was abnormal but not in the way I thought.  My wife and I ended the month with stinking colds so surely it was a colder April than but no, the Met Office insists it was above.  It was noticeably darker and wetter than normal with this April being the 6th wettest on record.
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6 Nations History #4 – The men’s story so far in 2024

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The 2024 Six Nations (Men’s) ended with Ireland just missing out on a 2nd successive Grand Slam due to a last minute drop goal.  Italy recorded their best ever 6 Nations and left Wales with the wooden spoon for the 2nd time ever.  France, England and Scotland recorded plusses and minuses during their campaigns and all 3 nations will be seeking to go one better in 2025.

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UK Weather Trends #30 – Winter 2024

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Winter 2024 in the UK was the 5th sunniest & 8th wettest on record.  A year ago I postulated UK winters were entering a new era of being warm, wet & sunny.  I am now certain this is the case and my favoured hypothesis is that our winters are following a steady trend which began in the early 1980s.

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UK General Election 2024 #1 – Going beyond the swing

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Labour is on course for a crushing landslide later this year… or are they?  Many parallels with 1997 are being drawn at the moment but it’s too early to be making detailed forecasts.  Instead, I want to lay the foundations for my election forecast later this year by looking at what 100 years of UK electoral history is telling me.  I tell this story by assigning probabilities to 10 specific outcomes of interest and finish by explaining why 2024 is more likely to be a repeat of 2001 than 1997.

I remind you I was deemed the most accurate forecaster of the 2019 general election.  This article is the first in what I hope will be a series of articles which lead me to hold on to that accolade!

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